Arrangement for the recovery of heat and water vapor in gaseous reactions



G. L. E. PATART ARRANGEMENT FOR THE RECOVERY OF HBAT AND WhTER VAPOR IN -GASEOUS- RBACTIONS Filed Jan. 14. 1925 z. 25 Gum 1 1 j Patented Feb. 26,`1929.

UNITED .STIATES PATENT OFFICE.

GEORGES mon EMILE ruana', or mms, FRANCE.

ARRANGEMENT FOR THE RECOVERY or HEAT .AND WATER VAPOR IN GASEOUS REACTIONS.

Application mea January 14, 19'25, serial No. 2,446, and in France January 21, 1924.

In certain gaseous reactions it is necessary v to employ an excess of water vapor and to preliminary heat the gases even though the reaction itself is exothermc so that a great 6 advantage Would be aforded by the simultancous recovery of the heatfand the water vapor which are withdrawn by the gases resulting from 'the reaction, in order to restore the same to the fresh gases which are to be 1'0 supplied to the apparatus. v This is particularly the case for the catalytic production of hydrogen by the process which is based upon the action of water vapor upon carbon monoxide in the presence of a Catalyst. The theoretical aid practical observation' of this 'eaction shows that advantageous results can only be obtained by the use' of triple or quadruple the amount of water vapor which is theoretically employed in the reaction'in each treatment by the catalyst, and further by maintain'ng the catalyzing chamber at a temperature near 500 C. I In order to carry the said process into effeet on an economicalscale, these two circumstances will require the maximum recovery of the excess-of water vapor which is mingled with the gas before circulating the same upon the Catalyst, and also of the heat withdrawn by the gases issuing from the catalyzng apparatus.

As concerns the recovery of the heat, this a may readil'y be efl'ected to a certain degree in the known temperature-exchanging devices of the tubular type. As regards the water vapor, this is usually recovered by treating the discharged gases with a shower of water which becomes heated while partially con-.

densing the water vapor; the water thus heated is subsequentl'y placed in intimate contact with the fresh gases supplied to the catalyzing apparatus, and the said gases thus become charged with a quantity of Water .va por corresponding to their pressure and to the temperature of the hot water used in the shower treatment of the said gases.

The present invention has for its object an arrangement for eflecting the said operation of the recovery of the watervapor and the leat to the maximum degree and in the most cconomical conditions.

The said ar'rangement consists essentially V vapor which they contain,

of a vertical apparatus comprising two superposed parts. In the upper part is effected firstly the cooling of the gases issuing from the catalyzing operation andthe condensation of the major part of the water heating of thecooling water; In the lower part there is efected firstly the heating of the fresh gases and the saturation of the same with water vapor at the maximum temperature and secondly the cooling of the water which has been heated in the upper part. The water thus cooled is collected at the bottom of the lower part of the apparatus and is elevated to the top of the upper part, and this cycle is repeated indefinitely, the excess of the condensed water vapor being optionally evacuated in a continuous manner as cold water. v a

The circulation of the gases is effected by and secondly the a'high power centrifugal device which aci a cordingto the -inventionserves to withdraw the gases which are heated at the top of the lower 'part of the apparatus-i. e. at the precise point at which they'are in contact with the water having the highest temperature-and to discharge the same at a sufliof the suction and delivery of thesaid een:

trifugal apparatus may optionally be reinforced by a steam ejector which is laced in series therewith and through whic the reuired excess of water vapor is supplied to t e circuit.

The water which is heated while circulating in the upper part of the apparatus descends to the top of the lower part of the apparatus through a siphon which forms the sole communication between the two parts of the apparatus. Both of these latter parts contain suitable devices afl'ording an intimate contact between the gases and the liquid, which devices may consist of chambers filled with coke; or of rings or spirals, but they are preferably (and according to the present invention) formed of bubbling plates which are provided with ca s and have small apertures therein which divde the gases into bubbles of very small size within the liquid which is circulating between the several plates.

The bottom bf the lower part forms a regulating reservoir in which a constant level can be maintained by means of an overflow' or by a regulated supply of cold water.

Throttl-e valves or other regulating valves which are nounted u on the inlet and the outlet conduit's allow o maintaining the pressure of the gases in the two parts of the column at the most favourable values according to the readings of the thermometers and presthe extent of the recovery which is desired.

The heated parts of the apparatus are well insulated.

The drawings accompanying the present description, which represent one of the constructional forms of the said device, are-given solely by way of example and in order to facilitate the comprehension of the preceding principles, and without limiting the scope of the said invention.

The said apparatus for the recovery of heat and vapor is herein represented as a gases become vertical column whereof 3 is the upper part and 4 the lower part, the bottom of the *upper part 3 being connected by an inverted siphon- 14, 15 with the top of the lower part 4, this latter having at the bottom the regulating reservoir 17. The gases supplied by the gas holder-and supposed tobe at theordinary temperature--a're withdrawn from the main conduit -1 through the branch Conduit 2; they enter at the bottom of the lower part 4: above the normal level of the regulating reservoir 17 the gases ascend through a set of bubbling plates receiving a downward current of heated vapor supplied from the to of the apparatus. During their upward ow, the heated and are saturated with water vapor, whilst the water is cooled when descending and' evaporating; if the number of plates is sufiicient, and the pressurewhich is produced at the upper part is sufliciently low, the difference in temperature between the water and the gases when entering and 'when leaving this region will be very small,

and the proportion of Water vapor withdrawn by the gases at their diseharge may be as great as desired. The gases are evacuated at the upper part of 4 through a conduit 5 leading to a centrifugalsuction fan 6 of high power which acts concurrently with a steam ejector 7 in order to introduce into the gases the additional amount of water vapor 'reqluired for the reactioL' The gases disc arged from the suction device and the ej ector are circulated into a catalyzing apparatus which is shown diagrammatically at 9 together with its accessories such as temperature, exchanging devices and the like. The gases issue therefrom at a high temperature together with 'an excess of water vapor which has notentcred into the reaction, and under the pressure produced by the discharge from 6, and they are circulated through the conduit 10 into the bottom part of the upper portion 3 of the recovery apparatus; the gases rise within the latter (as in the preceding case in the lower part) through a set of bubbling plates upon which is delivered the water which has been cooled during its circulation in the lower part, it having been taken up and then discharged into the top of the apparatus. During this traject, the gase's become cooled and yield up a portion of the water vapor which they contain, whilst the water becomes lreated during its descent in contact with the said gases. If the number of plates is suiicient and the quantity of water suitably determined, the temperature of the water on the lower plate will be very near the temperature of the gases entering the apparatus. y

The water which is cooled is colleeted in the regulating reservoir 17 Situated at the bottom of the lower part of the iapparatus, and is maintained therein ata constant level by means of a level gauge which is disposed at 18; the water is withdrawn by a purnp 19 which delivers it through the pipe 20 to the top of the upper part of the apparatus, and the eirculation then follows the same cycle as has been above described. A constant level is maintained in the reservoir 17 by means of an overflow 21 and a -cold water supply 22. As concerns the s eed of the circulation'of the gases and ther pressure, these may be regulated-independently of the speed of the -centrifugal device -by the throttle or like valves 23 and 24 mounted on the gas inlet and outlet conduits; furthermore, the branch 25 providesfor the regulation of the rate of the flow of the water upon the plates and therefore of the final temperatures in the 'two regions of the apparatus.

Obviously, the same recovery apparatus may be utilized 'with a plurality of catalysis apparatus. The centrfugal device 6 may have added thereto a second and like device 6' which is disposed'forwardly of the deliverv of the gases into the upper part of the co umn. v

What I claim is:

1.- In apparatus for the heating of fresh gases and for recovery of the water vapor pressure at said top,

contained in the gases, two superposed columns, bubbling plates in the columns, means to supply fresh gases to the lower part of the lower column for ascent theretlrough, means to withdraw the gases from column and maintain a sub-atmospheric means in which said gases are caused to react, means to conduct the resulting product to the bottom of the upper column and means to conduct the product from the top of the lattcr column after passage through the plates thei-ein and means to supply water from the bottom of each column to the top of the other column.

2. In apparatus for the heating of fresh gases and for the recovery of the Water contained in the gases ;two superposcd columns, bubbling plates in the columns, the lower colunn having a Water space below the plates thei-cin, means to supply fresh gases to the lower column below its platcs, means to withclraw the gases from the top of the lower column and maintain sub-atmospheric pressu'c thereat, a reaction chamber for receiving the withdrawn gases, means to conduct the products to the lower end ot the upper column, means to withdraw them from the upper end of the latter column, a spi-ay pipe at the top of the latter column, a pu'np connected to said water space and pipe, a spray pipe at the top of the lower column, a siphon connecting the bottom of the upper column and the top of said tlerein, means to supply fresh gases to the lower column below its plates, means to withdraw the gases from the top of the lower column and maintain sub-atmospheric pressure thereat, a reaction chamber for receiving the withdrawn gases, means to conduct the products to the' lower end of the upper column, means to withdraw them from the upper end of the latter column, a spray pipe at the top of the latter column, a pump connected to said water space and pipe, a spray pipe at the top of the lower column, a siphon connecting the bottom of the upper column and the latter spray pipe, Valves controlling. the entrance of the gas to the lower column and exit from the upper column, neans to maintain a constant level in the liquid space and a Valved by-pass between the suction and delivery side of said pump to control its effective delivery to the upper column.

In testimony that I clam the for'egoing as my invention, I have signed my name hereto.

GEORGES LEON -EMILE PATART. 

